混凝土路面嵌缝用RTV-1硅橡胶的研制

Preparation of RTV-1 Silicone Rubber for Caulking of Concrete Pavement

以不同黏度按一定比例混合的α,ω-二羟基聚二甲基硅氧烷和甲氧基封端聚二甲基硅氧烷为基胶,配合填料、增塑剂、扩链剂、交联剂、偶联剂、脱水剂和催化剂,制得低模量、高伸长率、粘接性能优越的单组分室温硫化硅橡胶。较佳配方为:复配基胶100份,混合填料80份,增塑剂50份,扩链剂8份,混合交联剂12份,偶联剂1. 5份,混合脱水剂6份。以此配方制得的硅橡胶拉伸强度为0. 11 MPa,拉断伸长率861%,弹性回复率95%,经紫外光老化处理(300 W,168 h,41℃)后,拉伸强度0. 15MPa,其性能满足《水泥混凝土路面嵌缝密封材料》的要求。

Low modulus, high elongation RTV-1 silicone rubber with excellent bonding properties was prepared by the base polymers, which was mixed with different viscosity and a certain proportion of α,ω-dihydroxy polydimethylsiloxane and methoxy-terminated polydimethysiloxane, mixing fillers, plasticizers, chain extenders, crosslinking agents, coupling agents, dehydrating agents and catalysts. The optimum formula was as follows： 100 phr of the base polymers, 80 phr of the mixed filler, 50 phr of the plasticizer, 8 phr of the chain extender, 12 phr of the mixed crosslinking agent, 1.5 phr of the coupling agent and 6 phr of the mixed dehydrating agent. The tensile strength, elongation at break, elastic recovery and tensile strength after UV aging （300 W, 168 h, 41℃） of silicone rubber are 0.11 MPa, 861%, 95% and 0.11 MPa, respectively. The properties of silicone rubber meets the requirements of Sealing Material for Cement Concrete Pavement Joints.